BauArf56
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How do i synthesize sodium peroxide?
I want synthesize Na2O2, but i haven’t many reagents. Can someone tell me some reaction that give sodium peroxide? Does Sodium carbonate and
hydrogen peroxide give that? Thanks
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teodor
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https://www.sciencemadness.org/whisper/viewthread.php?tid=10 ?
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Herr Haber
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That would give you the percarbonate.
The answer to your question is there:
https://en.wikipedia.org/wiki/Sodium_peroxide
UTFSE !
The spirit of adventure was upon me. Having nitric acid and copper, I had only to learn what the words 'act upon' meant. - Ira Remsen
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PirateDocBrown
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Set fire to sodium metal in air. Really, that's all there is to it.
Phlogiston manufacturer/supplier.
For all your phlogiston needs.
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Fantasma4500
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barium peroxide is made by fuming BaO with concentrated H2O2 fumes (60%+ iirc)
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AJKOER
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The action of H2O2 on NaOH suggests the path is as follows:
H2O2 = H+ + HO2-
HO2- + OH- = H2O + O2(2-)
where 30% H2O2 is favored as there is less starting water along with the use of concentrated NaOH.
I suspect low temperatures could remove the water, or perhaps by adding 95% alcohol as citing in one of the preps (link again https://www.sciencemadness.org/whisper/viewthread.php?tid=10). This results in a shift of the above reaction equilibrium to the right.
The presence of any carbonate ions is not favorable due to the creation of the percarbonate ion (see https://pubs.acs.org/doi/pdf/10.1021/ie0108752#targetText=wa... ) removing hydrogen peroxide:
HCO3- + H2O2 = HCO4- + H2O
--------------------------------------------
There is also a cited path to quote:
"the electrolysis of aqueous sodium hydroxide at temperatures between -10 and 0 degrees"
The reaction mechanics may proceed as follows with the electrolysis of the water present forming the •H (hydrogen atom radical) and oxygen:
•H + •H --> H2 (g)
And also importantly:
•H + O2 --> •HO2 --> H+ + •O2- ( pKa 4.88)
OH- + H+ = H2O (the added presence of OH- moves the above reaction to the right)
•O2- + e-(aq) --> O2(2-)
The implication of my proposed mechanics is that employing a medium that supports the OH- and presence of solvated electrons would be helpful.
Also, more generally, any path to the superoxide radical anion, •O2-, in the presence of solvated electrons, could be a path to peroxide.
Note, no carbonate presence as it can also remove •HO2 (and create a carbonate radical anion):
•HO2 + CO3(2-) = HO2- + •CO3-
[Edited on 9-9-2019 by AJKOER]
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Vomaturge
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How much H*, HO2*, and *HO2- do you expect to be in solution? and who's to stop it doing something or another to the alcohol involved, rather than
locking on to the actual sodium cation?
I think you may have a point with sodium hydroxide reacting with hydrogen peroxide, and even dehydrating with ethanol, although I'm not entirely sure
of the proposed reaction mechanism. I'll do a qualitative test if I find time tomorrow, just to be sure it doesn't decompose into oxygen gas. PubChem
says "Freely sol in water, forming sodium hydroxide and hydrogen peroxide, the latter quickly decomp into oxygen and water"
SM wiki says "The octahydrate can be easily prepared by a simple neutralization reaction with hydrogen peroxide (a weak acid) and sodium hydroxide. It
is recommended to use dilute solutions of hydrogen peroxide, because the side reaction of H2O2 decomposition becomes prevalent in concentrated
solutions. The crystals can be displaced out of solution with ethanol."
Hopefully, I'll soon know which is lying, or at least which one holds the most truth near standard temperature and pressure.
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Deathunter88
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Instead of synthesizing it you can buy a mine self rescue rebreather kit which will contain a container of sodium or potassium peroxide.
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Fleaker
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Really, this is of practical interest to me.
Sodium peroxide is an extremely clean and efficient reagent to (ultimately) generate ruthenates and osmates and to solubilize iridium and rhodium (in
acid milieu).
All of the sodium peroxide I use in analysis consists of yellow spherical prills. From a handling standpoint, they're rather ideal and they take some
time to hydrate and only slowly gain mass on an analytical balance.
Lately we have come to need this reagent in industrial quantities and have found it to be commercially unavailable here in the United States.
Obviously burning sodium with excess oxygen is the route, but there's certainly a trick to obtaining a product that is reasonably pure and controlling
what is a very exothermic reaction. The trick is oxygen and controlling the speed of the burn.
That said, I would like to try to make this reagent at the kilogram scale (for now).
Neither flask nor beaker.
"Kid, you don't even know just what you don't know. "
--The Dark Lord Sauron
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John paul III
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You can substitute Na2O2 for potassium peroxide. It can be made by heating potassium oxide with air. If you reacted potassium hydroxide with magnesium
powder you would get potassium metal which would quickly oxidize to potassium oxide. It is soluble in diethyl ether and in ethanol, so maybe you could
leach it out of the resulting aggregate and boil off the solvent and then heat it in air dried and decarboxylated with hydroxide
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ave369
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Quote: Originally posted by Vomaturge  | PubChem says "Freely sol in water, forming sodium hydroxide and hydrogen peroxide, the latter quickly decomp into oxygen and water"
SM wiki says "The octahydrate can be easily prepared by a simple neutralization reaction with hydrogen peroxide (a weak acid) and sodium hydroxide. It
is recommended to use dilute solutions of hydrogen peroxide, because the side reaction of H2O2 decomposition becomes prevalent in concentrated
solutions. The crystals can be displaced out of solution with ethanol."
Hopefully, I'll soon know which is lying
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It is an equilibrium. As soon as all ions stay in solution, the equilibrium is slowly shifted left, as the peroxide ion recombines into H2O2 and that
decomposes. As you crash the Na2O2 octahydrate crystals out of the solution, the equilibrium rapidly shifts right. It's simple Le Chatelier.
However, the octahydrate is not very useful anyway.
[Edited on 24-9-2019 by ave369]
Smells like ammonia....
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